gcc/testsuite/gcc.dg/pr36902.c

   1 /* PR middle-end/36902 Array bound warning with dead code after optimization */
   2 /* { dg-do compile } */
   3 /* { dg-options "-O2 -Warray-bounds -Wall -Wextra" } */
   4 typedef unsigned char __u8;
   5 typedef unsigned short __u16;
   6
   7 static inline unsigned char *
   8 foo(unsigned char * to, const unsigned char * from, int n)
   9 {
  10   switch ( n )
  11     {
  12     case 3:
  13       *to = *from;
  14       break;
  15     case 5:
  16       to[4] = from [4];
  17       break;
  18     }
  19   return to;
  20 }
  21
  22 struct {
  23   int    size_of_select;
  24   unsigned char pcr_select[4];
  25 } sel;
  26
  27 int bar(void)
  28 {
  29   static unsigned char buf[64];
  30
  31   sel.size_of_select = 3;
  32   foo(buf, sel.pcr_select, sel.size_of_select);
  33
  34   return 1;
  35 }
  36
  37
  38 static inline unsigned char *
  39 foo2(unsigned char * to, const unsigned char * from, int n)
  40 {
  41   switch ( n )
  42     {
  43     case 3:
  44       *to = *from;
  45       break;
  46     case 5:
  47       to[4] = from [4]; /* { dg-warning "array subscript is above array bounds" } */
  48       break;
  49     }
  50   return to;
  51 }
  52
  53 int baz(void)
  54 {
  55   static unsigned char buf[64];
  56
  57   sel.size_of_select = 5;
  58   foo2(buf, sel.pcr_select, sel.size_of_select);
  59
  60   return 1;
  61 }